Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add instructions/donnfelker/loop-skills/agents-mdgit clone --depth 1 https://github.com/donnfelker/loop-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/instructions/donnfelker/loop-skills/agents-md)<a href="https://agentmods.dev/instructions/donnfelker/loop-skills/agents-md"><img src="https://agentmods.dev/badge/instructions/donnfelker/loop-skills/agents-md.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.01257 | $0.01257 |
| Opus 5 | $0.00629 | $0.00629 |
| Sonnet 5 | $0.00251 | $0.00251 |
| Haiku 4.5 | $0.00126 | $0.00126 |
Grade A, and why
loop-skills AGENTS.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 98 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
Guidelines for AI agents working in this repository.
Repository Overview
This repository contains Agent Skills following the Agent Skills specification, packaged as a Claude Code plugin marketplace via .claude-plugin/marketplace.json.
- Name: loop-skills
- GitHub: donnfelker/loop-skills
- License: MIT
Every plugin here is a bounded autonomous loop: it drives an artifact to a terminal state, checks an explicit termination condition (quiet round, two clean passes, a cap), and commits per round for an audit trail.
Repository Structure
plugins/
└── plugin-name/
├── .claude-plugin/
│ └── plugin.json # Plugin manifest (name, description, version, license)
├── references/ # Optional - plugin-wide docs cited via ${CLAUDE_PLUGIN_ROOT}/references/...
└── skills/
└── skill-name/
├── SKILL.md # Required skill file (<500 lines)
├── references/ # Optional - skill-local docs loaded on demand
├── scripts/ # Optional - executable code
└── assets/ # Optional - templates, data files
Build / Lint / Test Commands
Skills are content-only (no build step). Validate with:
./validate-skills.sh plugins/*/skills/
Manually verify: YAML frontmatter is valid; name matches the directory exactly; name is 1-64 chars, lowercase alphanumeric and hyphens; description is 1-1024 characters.
Required Frontmatter
---
name: skill-name
description: What this skill does and when to use it. Include trigger phrases.
---
| Field | Required | Constraints |
|---|---|---|
name |
Yes | 1-64 chars, lowercase a-z, numbers, hyphens. Must match dir. |
description |
Yes | 1-1024 chars. Describe what it does and when to use it. |
license |
No | License name (default: MIT) |
metadata |
No | Key-value pairs (author, version, etc.) |
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 4d ago First seen · 98 lines · 1,257 tokens per session scan A 4e54b0118d75
loop-skills AGENTS.md is an instructions file published in the GitHub repository donnfelker/loop-skills (18 stars, last pushed 1mo ago), licensed MIT. It adds 1,257 tokens to every session, about $0.0063 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
next.js AGENTS.md
Instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.